Endoscopic instrument

ABSTRACT

An endoscopic instrument is provided and includes a housing including an elongated shaft assembly extending distally therefrom. The elongated shaft assembly includes inner and outer shaft members. The inner and outer shaft members are removably coupled to the housing and the outer shaft member is movable with respect to the inner shaft member. An end effector is operably supported at the distal end of the outer shaft member and includes a pair of jaw members configured for treating tissue. A bushing operably couples to the inner and outer shaft members of the shaft assembly and selectively and releasably couples to the housing. The bushing includes one or more mechanical interfaces configured to engage one or more slots defined through the inner shaft member and one or more slots defined through the outer shaft member to release the inner and outer shaft members from the housing.

CROSS REFERENCE TO RELATED APPLICATION

The present application claims the benefit of and priority to U.S.Provisional Application Ser. No. 61/677,348, filed on Jul. 30, 2012, theentire contents of which are incorporated herein by reference.

BACKGROUND

1. Technical Field

The present disclosure relates to endoscopic instruments and, moreparticularly, to endoscopic instruments including selectively removableshaft assemblies.

2. Background of Related Art

Endoscopic instruments are well known in the medical arts. For example,an electrosurgical endoscopic forceps (a closed forceps) is utilized insurgical procedures, e.g., laparoscopic surgical procedure, where accessto tissue is accomplished through a cannula or other suitable devicepositioned in an opening on a patient. The endoscopic forceps,typically, includes a housing, a handle assembly including a movablehandle, a shaft and an end effector assembly attached to a distal end ofthe shaft. The end effector includes jaw members configured tomanipulate tissue, e.g., grasp and seal tissues. The endoscopicinstrument may be configured to utilize one or more types of energiesincluding, but not limited to, RF energy, microwave energy, ultra soundto treat tissue.

Another type of endoscopic instrument that may be utilized inlaparoscopic surgical procedures is an ultrasonic endoscopic forceps.The ultrasonic endoscopic forceps is similar in configuration to theelectrosurgical endoscopic forceps. Unlike the electrosurgicalendoscopic forceps, however, the ultrasonic endoscopic forceps utilizesultrasonic energy to treat tissue.

As is conventional with both of the above endoscopic instruments, theshaft of these instruments is, typically, rigidly attached to theendoscopic instrument, i.e., the shaft is non-removable from thehousings of the respective instruments. Having an endoscopic instrumentwith a non-removable shaft may prove problematic during the operativelife cycle of the endoscopic instrument. For example, if the endoscopicinstrument is to be re-used, the entire device is, typically, sterilizedvia an autoclaving process or the like. As can be appreciated,sterilizing an endoscopic instrument with the shaft including the endeffector attached may prove difficult. In particular, it may provedifficult to sterilize between small spaces of the shaft, e.g., spacesat a distal end of the shaft adjacent the end effector.

SUMMARY

In view of the foregoing, it may prove advantageous in the medical artsto provide endoscopic instruments that include selectively removableshaft assemblies.

In the drawings and in the descriptions that follow, the term“proximal,” as is traditional, will refer to an end which is closer tothe user, while the term “distal” will refer to an end that is fartherfrom the user.

As used herein, “endoscopic instrument” generally refers to any surgicalinstrument that is configured for access into a body cavity. Theendoscopic instrument may be configured to grasp tissue or may beconfigured to grasp and subsequently electrosurgically treat tissue,e.g., an electrosurgical endoscopic device. In the latter instance, theendoscopic instrument may be configured to couple to one or moresuitable electrosurgical energy sources. Or, the endoscopic instrumentmay be battery powered. As it is used herein, “electrosurgicalprocedure” generally refers to any electrosurgical procedure involvingany form of energy, such as, for example, microwave energy,radiofrequency (RF) energy, ultrasonic energy, thermal energy orcombination thereof.

An aspect of the present disclosure provides an endoscopic instrument.The endoscopic instrument includes a housing including an elongatedshaft assembly extending distally therefrom. The elongated shaftassembly has inner and outer shaft members. The inner and outer shaftmembers are removably coupled to the housing and the outer shaft memberis movable with respect to the inner shaft member. An end effector isoperably supported at the distal end of the outer shaft member andincludes a pair of jaw members configured for treating tissue. A bushingmay be operably coupled to the inner and outer shaft members of theshaft assembly and configured to selectively and releasably couple tothe housing. In certain instances, the bushing may include one or moreresilient fingers that are configured to engage one or more slotsdefined through the inner shaft member and one or more slots definedthrough the outer shaft member to release the inner and outer shaftmembers from the housing. In certain instances, slot(s) on the outershaft member is/are longer than the slot(s) on the inner shaft member toallow the outer shaft member to translate with respect to the innershaft member.

A spring carrier includes one or more resilient bosses that areconfigured to releasably engage one or more second slots defined throughthe outer shaft member at a proximal end thereof to release the innerand outer shaft members from the housing when the outer shaft member isrotated with respect to the spring carrier. The spring carrier isconfigured to provide axial movement of the outer shaft member when ahandle assembly of the endoscopic instrument is actuated. In certaininstance, the resilient boss(es) includes a chamfered edge that isconfigured contact an edge of the corresponding second slot to move theresilient boss(es) out of engagement with the corresponding second slotwhen the outer shaft member is rotated. The spring carrier may include aplurality of radial slots on a distal face thereof. The plurality ofradial slots are configured to engage a corresponding plurality ofmating features disposed on an interior wall of the housing when thespring carrier is in a forward-most position within the housing.Engagement between the plurality of radial slots and correspondingplurality of mating features prevents rotation of the spring carrierwhen outer shaft member is rotated.

An aspect of the present disclosure provides an endoscopic instrument.The endoscopic instrument includes a housing that includes an elongatedshaft assembly extending distally therefrom. The elongated shaftassembly has inner and outer shaft members. The inner and outer shaftmembers are removably coupled to the housing and the outer shaft memberis movable with respect to the inner shaft member. An end effector isoperably supported at the distal end of the outer shaft member. Abushing is operably coupled to the inner and outer shaft members of theshaft assembly and is selectively and releasably coupled to the housing.The bushing includes a generally annular groove located at a proximalend thereof. A latch is operably disposed on the housing and is movablewith respect thereto for selectively and releasably engaging the annulargroove on the bushing to release the inner and outer shaft members fromthe housing.

The latch may include a pair of opposing arms. Each of the opposing armsmay include a respective detent that seats within a corresponding pocketdisposed within an interior wall of the housing. The detents may beseated within the pockets and configured to limit movement of the latch.

The latch may include an aperture that is configured to receive thebushing and the outer shaft member therethrough. Moreover, the latch mayinclude a generally elongated slot therein that is configured to engagea corresponding detent disposed on a locking member that is positionedproximal the latch and movable therewith. In this instance, the lockingmember may be configured to couple the outer shaft member to a springcarrier configured to provide axial movement of the outer shaft memberwhen a handle assembly of the endoscopic instrument is actuated. Theouter shaft member may include a flange disposed at a proximal endthereof that is configured to engage the locking member.

An aspect of the instant disclosure provides an endoscopic instrument.The endoscopic instrument includes a housing that includes an elongatedshaft assembly extending distally therefrom. The elongated shaftassembly has inner and outer shaft members. The inner and outer shaftmembers are removably coupled to the housing and the outer shaft memberis movable with respect to the inner shaft member. A rotating assemblyis operably coupled to the housing and is configured to rotate the innerand outer shaft members. A bushing is removably coupled to the rotatingassembly and is operably coupled to the inner and outer shaft membersand selectively and releasably coupled to the rotating assembly. An endeffector is operably supported at the distal end of the outer shaftmember. The bushing includes one or more mechanical interfaces that areconfigured to engage one or more slots defined through the inner shaftmember and at least one slot defined through the outer shaft member torelease the inner and outer shaft members from the housing.

The mechanical interfaces of the bushing may be in the form of one ormore resilient fingers. In this instance, the at least one slot on theouter shaft member is longer than the at least one slot on the innershaft member to allow the outer shaft member to translate with respectto the inner shaft member.

A spring carrier may be provided and may include at least one resilientboss. The resilient boss may be configured to releasably engage at leastone second slot defined through the outer shaft member at a proximal endthereof and configured to release the inner and outer shaft members fromthe housing when the outer shaft member is rotated with respect to thespring carrier. The at least one resilient boss may include a chamferededge that is configured to contact an edge of the corresponding secondslot to move the at least one resilient boss out of engagement with thecorresponding second slot when the outer shaft member is rotated. Thespring carrier may be further configured to provide axial movement ofthe outer shaft member when a handle assembly of the endoscopicinstrument is actuated. The spring carrier may include a plurality ofradial slots defined on a distal face thereof. The plurality of radialslots may be configured to engage a corresponding plurality of matingfeatures disposed on an interior wall of the housing when the springcarrier is moved to a forward-most position within the housing.Engagement between the plurality of radial slots and correspondingplurality of mating features prevents rotation of the spring carrierwhen outer shaft member is rotated.

The mechanical interfaces of the bushing may be in the form of one ormore detents. In this instance, the bushing may include a generallyannular groove that is located at a proximal end thereof.

A latch may be operably disposed on the housing and may be movable withrespect thereto for selectively and releasably engaging the annulargroove on the bushing to release the inner and outer shaft members fromthe housing. The latch may include a pair of opposing arms. Each of theopposing arms may include a respective detent that seats within acorresponding pocket disposed within an interior wall of the housing.The detents may be seated within the pockets and configured to limitmovement of the latch. The latch may include an aperture that isconfigured to receive the bushing and the outer shaft membertherethrough. The latch may include a generally elongated slot thereinthat is configured to engage a corresponding detent disposed on alocking member positioned proximal the latch and movable therewith. Thelocking member may be configured to couple the outer shaft member to aspring carrier configured to provide axial movement of the outer shaftmember when a handle assembly of the endoscopic instrument is actuated.The outer shaft member may include a flange that is disposed at aproximal end thereof that is configured to engage the locking member.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the present disclosure are described hereinbelowwith reference to the drawings, wherein:

FIG. 1 is a side, perspective view of an endoscopic instrument includinga selectively removable shaft assembly according to an embodiment of thepresent disclosure;

FIG. 2 is a side, perspective view of a proximal end of the shaftassembly depicted in FIG. 1 shown unattached from a housing of theendoscopic instrument;

FIG. 3 is a perspective view of a bushing that couples to inner andouter shaft members and to the housing of the endoscopic instrument;

FIG. 4 is a perspective view of a spring carrier that couples to theouter shaft member depicted in FIG. 2;

FIG. 5 is a side, perspective view of a selectively removable shaftassembly and bushing coupled thereto according to another embodiment ofthe instant disclosure;

FIG. 6 is a side view of an endoscopic instrument including theselectively removable shaft assembly and bushing depicted in FIG. 5;

FIG. 7 is an isometric view of the endoscopic instrument depicted inFIG. 6 with a latching mechanism shown in a latched configuration;

FIG. 8 is a side view of the of the endoscopic instrument depicted inFIG. 6 with the latching mechanism shown in a unlatched configuration;

FIG. 9 is an isometric view of the endoscopic instrument depicted inFIG. 8 with the latching mechanism shown in a unlatched configuration;and

FIG. 10 is the isometric view of FIG. 7 with the latching mechanismremoved to illustrate the position of the neighboring components of thelatching mechanism when the latching mechanism is in the latchedconfiguration.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Detailed embodiments of the present disclosure are disclosed herein;however, the disclosed embodiments are merely examples of thedisclosure, which may be embodied in various forms. Therefore, specificstructural and functional details disclosed herein are not to beinterpreted as limiting, but merely as a basis for the claims and as arepresentative basis for teaching one skilled in the art to variouslyemploy the present disclosure in virtually any appropriately detailedstructure.

As noted above, it may prove useful in the medical arts to provide anendoscopic instrument that includes a selectively removable shaftassembly. In accordance with the instant disclosure, a selectivelyremovable shaft assembly that may be configured for use with a varietyof endoscopic surgical instruments is provided. The selectivelyremovable shaft assembly includes a unique bushing configuration thatcouples to inner and outer shaft members of the shaft assembly to allowa user to remove the inner and outer shaft members from a housing of theendoscopic instrument. The unique bushing configuration also allowsaxial translation of the outer shaft member with respect to the innershaft member.

With reference to FIG. 1, an endoscopic instrument 2 that utilizes aselectively removable shaft assembly 4 according to an embodiment of theinstant disclosure is illustrated. For illustrative purposes, theendoscopic instrument 2 that is configured for use with the shaftassembly 4 is a battery powered ultrasonic instrument 2 (e.g., anultrasonic forceps 2). Briefly, forceps 2 includes a housing 6 that isconfigured to house one or more components, e.g., transducer, waveguideand electrical circuitry that is configured for electrical communicationwith a battery assembly 8 of the forceps 2. A proximal end of housing 6is configured to releasably couple to an ultrasonic generator 10 and thebattery assembly 8. A distal end of the housing 6 is configured tosupport and releasably couple to a proximal end 12 (FIGS. 1 and 2) ofshaft assembly 4 that is releasably positionable within a rotatingassembly 13. Shaft assembly 4 extends from housing 6 and defines alongitudinal axis “A-A” therethrough (FIG. 1). A distal end 14 of theshaft assembly 4 is configured to support an end effector 16 thereon.The operational parts of end effector 16 (e.g., jaw members 18 and 20)are movable relative to one another upon actuation of a movable handleassembly 22 coupled to housing 6.

In the illustrated embodiment, jaw member 20 serves as an active oroscillating blade and is configured to treat tissue. An activationbutton 24 places the forceps 2 in one or more modes of operation andgenerator 10 is configured to convert electrical energy produced by thebattery assembly 8 into ultrasonic energy. More particularly, generator10 includes a transducer (not explicitly shown) that is configured toconvert electrical energy to mechanical energy that produces motion in awaveguide (not explicitly shown) that is in operative communication withthe active jaw member 20.

With reference now to FIG. 2, the proximal end 12 of the shaft assembly4 is illustrated to show the operative components of the shaft assembly4. Shaft assembly 4 includes inner and outer shaft members 26 and 28respectively. In the illustrated embodiment, the inner shaft member 26encases an ultrasonic shaft (not explicitly shown). Unlike outer shaftmember 28 which is movable axially along the longitudinal axis “A-A” tomove jaw member 18, inner shaft 26 is fixed as it does not move axiallyto move jaw member 18. Rather, inner shaft 26 supports pivot points (notexplicitly shown) for jaw member 18 to open and close. The ultrasonicshaft member is rigidly coupled to the housing 6 and is configured tohouse one or more components of the forceps 2, e.g., the waveguideand/or transducer therein. In some embodiments, however, the ultrasonicshaft may be configured to releasably couple to the housing 6.

Outer shaft member 28 is configured to support the jaw members 18 and 20thereon (FIG. 1) and is configured to releasably couple to one or morecomponents, e.g., a spring carrier 42 (FIG. 4), of the housing 6. Thus,after use, the inner shaft member 26 and outer shaft member 28(including the jaw members 18 and 20 supported thereon) may be removedfrom the housing 6 so that the housing 6 including the ultrasonic shaftmay be sterilized. As noted above, outer shaft 28 moves axially alongthe longitudinal axis to open and close jaw member 18.

One or more slots 30 are defined through the inner shaft member 26 andare aligned with one or more corresponding first slots 32 definedthrough the outer shaft member 28 (FIG. 2). Slots 30 and 32 may includeany suitable configuration. In the illustrated embodiment, slots 30 and32 include a generally elongated configuration. In accordance with theinstant disclosure, slots 30 are smaller in length than slots 32, asbest seen in FIG. 2. Providing slots 30 with a smaller length allows theouter shaft member 28 to move axially a predetermined distance withrespect to the inner shaft member 26 to move the jaw member 18 from anopen configuration (FIG. 1) to a closed configuration (not explicitlyshown). Specifically, slots 30 are completely filled by a boss 50 onbushing 36 to restrict axial movement of inner shaft member 26. Firstslots 32 are longer than slots 30 to allow axial movement of outer shaftmember 28 to move jaw member 18 from the open configuration to closedconfiguration. As can be appreciated, first slots 32 can be sized tolimit a maximum opening of jaw member 18.

With reference to FIG. 3, a bushing 36 is illustrated including a base38 and an elongated stem 41 extending distally therefrom. Bushing 36 isconfigured to fixedly couple to the inner and outer shaft members 26,28. Accordingly, corresponding mechanical interfaces (e.g., resilientfingers 34) are disposed on stem 41 and are biased radially inwardtherefrom to engage slots 30 and 32 on the respective inner and outershaft members 26, 28.

Base 38 is configured to key the bushing 36 to the rotation of therotating assembly 13. Accordingly, base 38 includes a plurality ofplanar surfaces 38 a (or splines not explicitly shown) that areconfigured to engage corresponding surfaces of the rotating assembly 13.In the embodiment illustrated in FIG. 3, the base 38 includes eight (8)planar surfaces 38 a forming a generally octagonal configuration.

An aperture 40 of suitable configuration extends through the bushing 36and is configured to receive the outer shaft member 28 therethrough forcoupling the outer shaft member 28 to the spring carrier 42 (FIG. 4).

Spring carrier 42 includes a generally elongated proximal end 44 ofsuitable configuration that is configured to support a spring (notexplicitly shown) thereon (FIG. 4). One or more resilient bosses 50 (oneresilient boss 50 illustrated in the drawings) extend radially inwardfrom the elongated proximal end 44 (FIG. 4) and are configured toreleasably couple to one or more corresponding slots 52 disposed at theproximal end 12 of the outer shaft member 28 (FIG. 2). The resilientbosses 50 include a chamfered edge 53 (FIG. 4) that is configured tofacilitate engaging and disengaging the outer shaft member 28 with thespring carrier 42. In particular, as the outer shaft member 28 isrotated (e.g., counter-clockwise) an edge 15 (FIG. 2) of the outer shaftmember 28 that defines the slots 52 cams the resilient boss 50outwardly.

Spring carrier 42 also includes a generally circumferential distal end46 that is configured to engage an internal wall (not explicitly shown)of the housing 6. In particular, a plurality of radial slots 54 areformed in a distal face 56 of the spring carrier 42 and are configuredto engage corresponding mating features (not explicitly shown) on theinternal wall of the of the housing 6. More particularly, when themovable handle 22 is moved proximally, the spring carrier 42 is moveddistally toward the distal end of the housing 6 (e.g., the springcarrier 42 is moved to an extreme forward position) and into engagementwith the mating features on the internal wall of the housing to “lock”the spring carrier 42 and prevent the spring carrier 42 from rotatingwith the outer shaft member 28.

In use, after a surgical procedure, e.g., an ultrasonic sealingprocedure, has been completed, the bushing 36 including the inner andouter shaft members 26, 28 may be removed so that the housing 6 andultrasonic shaft coupled thereto may be completely cleaned andre-sterilized by an autoclave. In one embodiment, the moveable handle 22is moved proximally to move the spring carrier 42 to the extreme forwardposition to lock the spring carrier 42 as described above. With thespring carrier 42 in the locked position, the outer shaft member 28 maybe rotated, e.g., in a counter-clockwise direction, to disengage theresilient bosses 50 from the slots 52 of the outer shaft member 28. Oncethe resilient bosses 50 are disengaged from the slots 52, the bushing 36including the inner and outer shaft members 26, 28 may be uncoupled fromthe housing 6.

To re-attach the bushing 36 including the inner and outer shaft members26, 28 (or in some embodiments, a new bushing 36 including new inner andouter shaft members 26, 28 with new seals), the bushing 36 including theinner and outer shaft members 26, 28 may be slid over the ultrasonicshaft and the outer shaft member 28 may be reinserted into the springcarrier 42. Once inserted into the spring carrier 42, the outer shaftmember 28 may be rotated, e.g., in a clockwise direction, to engage theresilient bosses 50 with the slots 52 of the outer shaft member 28.

The unique configuration of the bushing 36 and shaft assembly 4 of thepresent disclosure enables a user to quickly and easily couple anduncouple the bushing 36 including the inner and outer shaft members 26,28 from the housing 6 of the forceps 2 for sterilization of the forceps2.

With reference to FIGS. 5-10 a shaft assembly 104 according to analternate embodiment of the present disclosure is illustrated. Forceps102 and shaft assembly 104 are substantially similar to forceps 2 andshaft assembly 4. In view thereof, only those features unique to theforceps 102 and/or shaft assembly 104 are described in detail.

Unlike outer shaft member 28, outer shaft member 128 includes a proximalflange 129 of suitable configuration (FIG. 5). Proximal flange 129 isconfigured for engagement with a “guillotine” type locking member 131that is operably coupled to a spring carrier 142 (FIGS. 6, 8 and 10) tocouple the outer shaft member 128 to the spring carrier 142. In oneembodiment, the locking member 131 slides over a front face 133 (FIG. 5)of the proximal flange 129 to couple the outer shaft member 128 to thespring carrier 142. This method for coupling the outer shaft member 128to the spring carrier 142 allows the proximal flange 129 to freelyrotate behind the locking member 131 such that the spring carrier 142does not rotate with the outer shaft member 128.

Locking member 131 includes a bottom portion with a generally “C-shaped”configuration that rests on an outer surface of the outer shaft member128, see FIG. 10 for example. This “C-shaped” configuration allows thelocking member 131 to move in and out of engagement with the outer shaftmember 128 and allows the outer shaft member 128 to move axially withthe spring carrier 142.

A top portion 135 (FIGS. 6, 8 and 10) of the locking member 131 includesa detent 137 (FIGS. 6-10) that is configured to engage a correspondingaperture 139 (FIG. 7) on a latch 141 (FIGS. 6-9). The detent 137 andaperture 139 couple the locking member 131 to the latch 141 to allow thelocking member 131 and latch 141 to move in unison.

The latch 141 is operably disposed in the housing 106 and is accessibleto a user from a top portion of the housing 106. The latch 141 alsoincludes an aperture 143 of suitable configuration that allows passageof the bushing 136 including the outer shaft member 128 therethrough(FIGS. 7 and 9).

An interior wall 151 (FIGS. 7 and 9) that defines the aperture 143 isconfigured to releasably engage an annular groove 145 (as best seen inFIG. 5) disposed at a proximal end 147 of the bushing 136. Inparticular, pulling the latch 141 a predetermined distance (e.g.,upwards) disengages the interior wall 151 from the annular groove 145and disengages the flange 129 from the locking member 131 so that thebushing 136 including the inner and outer shaft members 126, 128 may beuncoupled from the spring carrier 142. Likewise, pushing the latch 141 apredetermined distance (e.g., downwards) engages the interior wall 151with the annular groove 145 and engages the flange 129 with the lockingmember 131 so that the bushing 136 including the inner 126 and outershaft members 128 may be coupled to the spring carrier 142.

Unlike bushing 36 that includes a pair of resilient fingers 34, thebushing 136 includes a pair of mechanical interfaces (e.g., detents 134)that are configured to engage corresponding slots 130 and 132, see FIGS.5, 6 and 8; in these figures, the detent 134 is shown engaged with theslot 130 and as such the slot 130 is not explicitly shown.

A guide slot 152 (FIG. 5) is provided to replace slot 52 of the outershaft member 28 and is configured to engage a corresponding detent 156that extends from the spring carrier 142 (FIG. 9). This configuration ofthe guide slot 152 and detent 156 facilitates aligning the annulargroove 145 and the inner wall 151 of the locking member 131.

A stop member 158 (FIGS. 6 and 8) defined on an interior surface of thehousing 106 is provided and is configured to contact the top surface 135of the locking member 131 when the latch 141 has been pulled apredetermined distance (e.g., upwards), see FIG. 8 for example; thisprevents a user from “over-pulling” the latch 141.

In some embodiments, such as the one illustrated in FIGS. 5-10, thelatch 141 includes an optional pair of opposing arms 153 that eachinclude a respective detent 155 (see FIG. 9 for example) that seatswithin a corresponding pocket (not explicitly shown) disposed within aninterior wall of the housing. The detents 155 seated within the pocketsare configured to further limit movement of the latch 141.

In use, to uncouple the bushing 136 including inner and outer shaftmembers 126, 128 from the housing 106, a user pulls the latch 141 (e.g.,upwards) to disengage the locking member 131 from the proximal flange129 and the latch 141 from the annular groove 145.

Once disengaged, the bushing 136 including inner and outer shaft members126, 128 may be uncoupled from the housing 106.

To re-couple the bushing 136 including inner and outer shaft members126, 128 to the housing 106, the user re-inserts the bushing 136including inner and outer shaft members 126, 128 into the housing 106and pushes the latch 141 (e.g., downwards) to engage the locking 131member with the proximal flange 129 and the latch 141 with the annulargroove 145.

As described above with respect to the bushing 36 and shaft assembly 4,the unique configuration of the bushing 136 and shaft assembly 104 ofthe present disclosure enables a user to quickly and easily couple anduncouple the bushing 136 including the inner and outer shaft members126, 128 from the housing 6 of the forceps 102 for sterilizationthereof.

From the foregoing and with reference to the various figure drawings,those skilled in the art will appreciate that certain modifications canalso be made to the present disclosure without departing from the scopeof the same. For example, and as noted above, the ultrasonic shaft maybe configured to couple and uncouple with the bushings 36, 136 includinginner and outer shafts 26, 126 and 28, 128, respectively. In thisinstance, one or more components associated with the forceps 2, 102 maybe utilized in conjunction with the shaft assemblies 4, 104. Forexample, in one particular embodiment, a rear knob 3 (FIG. 1) may beutilized to release the ultrasonic shaft. In this instance, the rotatingassemblies 13, 113 are held immobile while the rear knob 3 is turned tounscrew the ultrasonic shaft. Once the ultrasonic shaft is unscrewed, italong with the shaft assemblies 4, 104 may be uncoupled as describedabove.

While several embodiments of the disclosure have been shown in thedrawings, it is not intended that the disclosure be limited thereto, asit is intended that the disclosure be as broad in scope as the art willallow and that the specification be read likewise. Therefore, the abovedescription should not be construed as limiting, but merely asexemplifications of particular embodiments. Those skilled in the artwill envision other modifications within the scope and spirit of theclaims appended hereto.

1-20. (canceled)
 21. An endoscopic instrument, comprising: a housing; aspring carrier supported within the housing; a shaft assembly configuredfor releasable engagement with the housing and the spring carrier, theshaft assembly including first and second shaft members and a bushing,the bushing slidably engaged to the first shaft member and fixedlyengaged to the second shaft member such that the first shaft member isslidable relative to the second shaft member and the bushing; an endeffector supported at a distal end of the shaft assembly; and a lockingmechanism including a first locking component and a second lockingcomponent, the locking mechanism transitionable from an unlockedcondition permitting insertion and removal of the shaft assembly fromthe housing, and a locked condition, wherein the first locking componentengages the first shaft member with the spring carrier such thatactuation of the spring carrier effects axial movement of the firstshaft member, and the second locking component engages the busing withthe housing to longitudinally fix the bushing and the second shaftmember relative to the housing.
 22. The endoscopic instrument accordingto claim 21, wherein the second shaft member is coaxially disposedwithin the first shaft member.
 23. The endoscopic instrument accordingto claim 21, wherein the bushing defines an annular groove and wherein,in the locked condition, the second locking component is engaged withinthe annular groove to longitudinally fix the bushing and the secondshaft member relative to the housing.
 24. The endoscopic instrumentaccording to claim 23, wherein the second locking component is a latchdefining an aperture configured to receive the bushing therethrough. 25.The endoscopic instrument according to claim 23, wherein the bushing isrotatable relative to the housing when engaged therewith.
 26. Theendoscopic instrument according to claim 21, wherein the first shaftmember includes a proximal flange and wherein the first lockingcomponent, in the locked condition, is configured to engage the proximalflange with the spring carrier to thereby engage the first shaft memberwith the spring carrier.
 27. The endoscopic instrument according toclaim 26, wherein the first locking component is a C-shaped lockingmember.
 28. The endoscopic instrument according to claim 26, wherein thefirst shaft member is rotatable relative to the spring carrier whenengaged therewith.
 29. The endoscopic instrument according to claim 21,wherein the first and second locking components are fixedly engaged withone another.
 30. The endoscopic instrument according to claim 29,wherein at least a portion of the first locking component or the secondlocking component extends from the housing to enable manual manipulationthereof to transition the locking mechanism between the locked conditionand the unlocked condition.
 31. The endoscopic assembly according toclaim 21, wherein the end effector includes an ultrasonic jaw member anda clamping jaw member, the clamping jaw member movable relative to theultrasonic jaw member between a spaced-apart position and anapproximated position in response to sliding of the first shaft memberrelative to the second shaft member.
 32. The endoscopic assemblyaccording to claim 31, further comprising a handle operably coupled tothe housing and the spring carrier, the handle movable relative to thehousing to actuate the spring carrier to, in turn, slide the first shaftmember relative to the second shaft member.